X5 4.4 - Sludge in engine and oil filter housing... help!

[FSETH]

Originally Posted by sunny5280

That's fine. I do not. And without evidence to the contrary it will remain an urban legend in my mind.

I really don't think you would ever believe there was an issue with this if your mechanic said so himself.

I've spoken to my mechanic, who has 25 years repairing BMWs, about this issue. He doesn't feel there is any risk to changing the fluid. And he has done it many, many times.

Even JCL has qualified the risk as slight.

Once again, how do we know your mechanic is reputable. Many indy mechanics say there is no problem with changing the fluid. There was another thread posted here a few weeks back where someones "reputable" mechanic told them Mobil 1 was the best oil for BMW's...



That is their right. I'm not surprised to hear there are some shops which believe this urban legend.

Like I said, there is eveidence pointing to the contrary, it just doesn't mesh with your personal bias. You do seem somewhat disrespectful by the way your repeat urban legend over and over.

[sunny5280]

Originally Posted by FSETH

Like I said, there is eveidence pointing to the contrary, it just doesn't mesh with your personal bias. You do seem somewhat disrespectful by the way your repeat urban legend over and over.

I have seen no evidence. What I have seen is a theory put forth by JCL. Of which he has refused to provide data in support of it. While his theory sounds plausible I believe it is so only in a handful of incidents. Unless he wishes to provide supporting data or reference to some other supporting data I will continue to view this as nothing more than an urban legend. And if calling it such leads you to conclude I'm being disrespectful, well, there's nothing I can do about that.

[FSETH]

sunny, Are you a BMWCCA member? If so, I HIGHLY suggest e-mailing tech-talk and getting a copy of their old school maintenance schedule. It is written by Mike Miller who is more than likely a better BMW mechanic than your guy seeing as he does the mechanical questions for both Roundel and Bimmer magazine. In the maintenance schedule, he flat out states that it is risky to drain a previously unmaintained automatic transmission with higher mileage. Pretty much stating what everyone else here is trying to tell you that he has personally seen TOO MANY properly functioning automatic transmissions go shortly after a filter and fluid change. Shifting of sludge is just one of the reasons he states it can happen.

and like JCL pointed out, he goes on to say that he has seen properly maintained transmissions break anyway and that there is just no predictiing them. He says he has seen un-maintained as well as properly maintained units both go 200k. Unfortunately, I can't post this PDF from the CCA as they ask you not to, but you can obtain a copy with your $20 membership. There is over a page dedicated to automatic transmission maintenance. Maybe you could print it out and take it to your mechanic?

Pretty much like we all have said in this thread. There is no right answer when it comes to changing the trans fluid and you should do what makes you happy, but calling the risk of changing fluid on a higher mileage BMW that has not been maintained an urban myth, is just flat out inaccurate.

[sunny5280]

Originally Posted by FSETH

sunny, Are you a BMWCCA member? If so, I HIGHLY suggest e-mailing tech-talk and getting a copy of their old school maintenance schedule. It is written by Mike Miller who is more than likely a better BMW mechanic than your guy seeing as he does the mechanical questions for both Roundel and Bimmer magazine. In the maintenance schedule, he flat out states that it is risky to drain a previously unmaintained automatic transmission with higher mileage. Pretty much stating what everyone else here is trying to tell you that he has personally seen TOO MANY properly functioning automatic transmissions go shortly after a filter and fluid change. Shifting of sludge is just one of the reasons he states it can happen.

and like JCL pointed out, he goes on to say that he has seen properly maintained transmissions break anyway and that there is just no predictiing them. He says he has seen un-maintained as well as properly maintained units both go 200k. Unfortunately, I can't post this PDF from the CCA as they ask you not to, but you can obtain a copy with your $20 membership. There is over a page dedicated to automatic transmission maintenance. Maybe you could print it out and take it to your mechanic?

Pretty much like we all have said in this thread. There is no right answer when it comes to changing the trans fluid and you should do what makes you happy, but calling the risk of changing fluid on a higher mileage BMW that has not been maintained an urban myth, is just flat out inaccurate.

So with everything you said you couldn't point me to one piece of evidence?

Look, I'm not saying there is absolutely zero risk with replacing the fluid. As with anything there is a risk. I have repeatedly acknowledge there is some risk. And, like JCL, I feel that risk is slight (that is his qualification, not mine).

As for my guy he owns his own business and has been doing transmission fluid changes for years. I think he's more than qualified to have an opinion on the subject.

Also stating fluid changes have benefit is not the same as saying you will never have a problem with the transmission. That would be akin to saying that changing your engine oil will result in zero problems with your engine. I don't think any of us would say that...do you? So why would you make the same argument with transmissions?

Perhaps if you explain why new transmission fluid is likely to dislodge sediment whereas old fluid will not maybe I could see the risk changing from slightly to a more likely possibility. Can you do that?

JCL also alluded to thinner fluid and improperly performed fluid replacement. Perhaps the issue has more to do with incorrect fluids or work being performed than it does with merely doing the work. My assumption is the correct fluids being used and the work being done properly.

[Penguin]

Originally Posted by FSETH

sunny, Are you a BMWCCA member? If so, I HIGHLY suggest e-mailing tech-talk and getting a copy of their old school maintenance schedule. It is written by Mike Miller who is more than likely a better BMW mechanic than your guy seeing as he does the mechanical questions for both Roundel and Bimmer magazine. ... There is no right answer when it comes to changing the trans fluid and you should do what makes you happy, but calling the risk of changing fluid on a higher mileage BMW that has not been maintained an urban myth, is just flat out inaccurate.

I also like Mike Miller and rarely disagree with his take on things -- he obviously is extremely experienced with BMWs.

Now, I don't particularly want to get into the middle of things, as AT fluid change is almost as controversial as which brand of engine oil and how often to change it, but there is a piece of information I'd really like to know if anyone has the answer.

Did BMW change their recommendation for AT fluid changes from Lifetime/never to 100,000 miles? I seem to recall reading that, but can't find a confirmation with a search.

P.S. For anyone who hasn't gotten enough of the AT change discussion, this link should keep ya' busy for a while!

Collecting Statistics on BMW auto transmission and Lifetime ATF - Bimmerforums - The Ultimate BMW Forum

[X5 Meister]

This thread is beating a long dead horse, but perhaps it's still an interesting discussion with some very valuable information. Let me just interject a couple of my observations/concerns:

1. I think there is certainly some strong credibility in the don't change the fluid in a non-maintained transmission, the question is, just what constitutes a properly maintained transmission where one wouldn't be at risk, or at least significantly lesser risk, of dislodging sediment? IOW, what's the magic cut-off mileage or age? Regular 10,000 mile changes, 15,000 mile, 20,000 mile, yearly, etc? With this I think I'd be more interested in hearing from ZF than BMW.

2. Given that BMW specifically states lifetime fill on the transmission, one concern I might have is that if I did change the fluid, and something went wrong with the transmission, would they cover it under warranty since they specifically said not to mess with it?

3. Not to add a 3rd component into the mix (engine oil, transmission fluid, and now...) but beginning 2004 model year BMW suddenly went to lifetime fill for the cooling system. Marketing decision? Does it fall under the same circumstances as transmission maintenance, etc?

4. While BMW seems to be gradually moving to completely maintenance free cars (at least on paper, especially when you are on a 3 year lease!) it appears that as newer engines come into play they are stepping up some maintenance schedules. Here is an interesting list of the 2011 model year maintenance schedules just as an FYI...

For the 335is (Coupe and Convertible), Z4 sDrive35is, and 740i/Li with the N54T engine:

• There is no 1200 Mile Service.
• Engine oil is the same as for the 335i (recommended: BMW High Performance 5W-30 Synthetic oil P/N 07 51 0 017 866)
• Spark plug replacement interval is 45,000 miles or at every 3rd engine oil service.
• Engine air filter replacement interval is at every 2nd engine oil change.

For the 135i (all versions), 335i (all versions), and 535i with the N55 engine:

• Spark plug replacement interval is 60,000 miles or at every 4th engine oil service.
• Engine air filter replacement interval is at every 2nd engine oil change.

BMW ALPINA B7:

• There is no 1200 Mile Service.
• Spark plug replacement interval is 30,000 miles or at every 2nd engine oil service.
• Engine air filter replacement interval is at every 2nd engine oil change.

Vehicle check: Check the expiration date on the M Mobility System sealant bottle. Change the bottle if needed.

ActiveHybrid 7: Maintenance is comparable to a 750i.

Spark Plug Replacement Intervals

2011 Model Engine Interval (miles); coincides with every _ Engine Oil change

128i, 328i, Z4 sDrive30i N52TU 60,000; 4th

135i, 335i, 535i N55 60,000; 4th

Z4 sDrive35i N54 45,000; 3rd

335is, Z4 sDrive35is, 740i N54T 45,000; 3rd

M3 S65 37,500; 3rd (first oil change is at 1200 miles)

550i, 750i, ActiveHybrid 7 N63 60,000; 4th

760Li N73 60,000; 4th

BMW ALPINA B7 N63B44M1 30,000; 2nd

[FSETH]

Originally Posted by sunny5280

So with everything you said you couldn't point me to one piece of evidence?

Look, I'm not saying there is absolutely zero risk with replacing the fluid. As with anything there is a risk. I have repeatedly acknowledge there is some risk. And, like JCL, I feel that risk is slight (that is his qualification, not mine).

As for my guy he owns his own business and has been doing transmission fluid changes for years. I think he's more than qualified to have an opinion on the subject.

Also stating fluid changes have benefit is not the same as saying you will never have a problem with the transmission. That would be akin to saying that changing your engine oil will result in zero problems with your engine. I don't think any of us would say that...do you? So why would you make the same argument with transmissions?

Perhaps if you explain why new transmission fluid is likely to dislodge sediment whereas old fluid will not maybe I could see the risk changing from slightly to a more likely possibility. Can you do that?

JCL also alluded to thinner fluid and improperly performed fluid replacement. Perhaps the issue has more to do with incorrect fluids or work being performed than it does with merely doing the work. My assumption is the correct fluids being used and the work being done properly.

I am not sure what type of proof you are looking for? What will it take? Mike Miller is the technical editor for BMWCCA's Roundel magazine. The BMWCCA has over 80,000 members. He answers up to 50 technical questions per day (according to himself) and about 3-5 pages make it into the magazine every month. He is also a contributing editor for Bimmer magazine where he answers additional technical letters. I think he did, or currently does, the same for European Car as well. Basically, I am saying that his data base dwarfs your mechanic's. Therefore, he should be better able to analyze trends, especially where BMW's are concerned. Like I said before, I wish I could post the entire PDF, but I cant. In it, he states very clearly that he has seen all too many times where where a well-meaning owner or technician performs an ATF and filter service on a neglected but well-shifting automatic, and then all of the sudden it starts slipping. He goes on to say that he feels a contributing factor of this is that the fresh ATF flushes a bit of sludge from a place where it was doing no harm to a place where it does do harm. He also see's overfilling, underfilling, and cleanliness as issues.

He also goes on to say that the fluid in BMW's "lifetime fill" automatics is proprietary info and highly recommends that the a dealer performs this service as no one knows exactly what BMW's proprietary ATF is. As I pointed out before, he states that not even all dealers will want to touch the trans fluid, not just typical shops that are buying into the "urban legend" as you say.

You don't have to take my word for any of this. Become a BMWCCA member and you can have access to the full article in no time. I am glad that you are finally realizing the risk is real and is not simply an urban myth as you said multiple times before.

Also, with some BMW automatic transmissions seeing 200k+ miles on the original fluid (think we have a few here) as well as the dime a dozen 100k+ on original fluid here, the fluid itself is no the main concern. Like JCL has said, the other components are going to fail before the fluid and changing the fluid every 30k miles is not guaranteed to make the trans last any longer.

[FSETH]

Originally Posted by Penguin

Did BMW change their recommendation for AT fluid changes from Lifetime/never to 100,000 miles?

Yes, they sure did, but I am not positive when that was.

[FSETH]

Originally Posted by X5 Meister

This thread is beating a long dead horse, but perhaps it's still an interesting discussion with some very valuable information. Let me just interject a couple of my observations/concerns:

1. I think there is certainly some strong credibility in the don't change the fluid in a non-maintained transmission, the question is, just what constituted a properly maintained transmission where one wouldn't be at risk, or at least significantly lesser risk, of dislodging sediment? IOW, what's the magic cut-off mileage or age? Regular 10,000 mile changes, 15,000 mile, 20,000 mile, yearly, etc?

I would guess mileage would be more important seeing as it is a sealed system. It is different than say engine oil. I think MM recommends changing "lifetime fill" ATF every 30k if you are going to do it. I probably wouldn't go much further than that if I were planning on changing it. I decided to leave mine alone just after 70k, which I felt was "higher milage" at over double his recommended interval.

2. Given that BMW specifically states lifetime fill on the transmission, one concern I might have is that if I did change the fluid, and something went wrong with the transmission, would they cover it under warranty since they specifically said not to mess with it?

Another good question.

3. Not to add a 3rd component into the mix (engine oil, transmission fluid, and now...) but beginning 2005 model year BMW suddenly went to lifetime fill for the cooling system. Marketing decision? Does it fall under the same circumstances as transmission maintenance, etc?

I would think changing out the coolant doesn't involve any real risk of damage or failure to the cooling system regardless of maintenance/non-maintenance. I would change mine, personally.

[X5 Meister]

I'd have to double check but I know that from 2002+ it was 100,000 miles and not lifetime.

Coolant change interval went from 4 years in 2003 to lifetime in 2004+.

Originally Posted by FSETH

Yes, they sure did, but I am not positive when that was.